Plant thinning machine



Jan. l5, 1952 L. B. swAFFoRD 2,582,513

PLANT THINNING MACHINE Jan. l5, 1952 l.. B. swAFFoRD PLANT THINNING MACHINE 5 Sheebs-Sheml 2 Filed June 29, 1948 INVENTOR.

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Jan. 15, 1952 L, B, SWAP-FORD 2,582,513

PLANT THINNING MACHINE Filed June 29, 1948 5 Sheets-Sheet 3 INVENTOR.

Jan- 15, 1952 1... B. SWAFFORD 2,582,513

PLANT THINNING MACHINE Filed June' 29, 1948 5 Sheets-Sheet 4 JNVENTOR. aer fu/affare? .Jan- 15 1952 B. swAFFoRD 2,582,513

PLANT THINNING MACHINE Filed June 29, 1948 5 Sheets-Sheet 5 INVENTOR.

Patented Jan. 15, 1952 UNITED STATES PATENT OFFICE PLANT THINNING MACHINE Luther B. Swazord, England, Ark.

Application June 29, 1948, Serial No. 35,945

1 4 claims. 1

This invention relates to improvements in agf ricultural implements, and more particularly to improved tractor attachments for cultivating and chopping or thinning row crops, such as cotton.

It is among the objects of the invention to provide an improved cotton chopping and cultivatf ing attachment for a farm tractor, which attachment is effective to shape the rows or ridges in which the cotton plants grow, mechanically cut off and destroy the plants at spaced-apart intervals along the row to thin the plants and restrict A,

them to uniformly-spaced hills, which severs the plants at or slightly below the surface of the ground to avoid recurrence of growth of the severed plants, which is fully automatic in operation, adjustable to different row spacings, easily' applied to and removed from a conventional tractor and operatively connected to the implement mechanism ofthe tractor, which cultivates and thins two rows of plants at the same time and which is strong, rigid and durable in construe-l tion and extremely economical to manufacture.

Other objects and advantageswll become apparent from a consideration of the following description and the appended claims, in conjunction with the accompanying drawings, wherein:

Figure 1 is a top plan view of a conventional farm tractor with a crop-thinning and cultivating attachment illustrative of the invention operatively applied thereto;

Figure 2 is a side elevation of the tractor and Figure 5 is a transverse cross-section taken substantially on the line 5--5 of Figure 4;

Figure 6 is a transverse cross-section taken sub stantially on the line 6--6 of Figure 4;

Figure 7 is a top plan view of an enlarged scale of a fragmentary portion of the attachment frame illustrating a structural detail of the frame, a portion being broken away yand shown in cross section to better illustrate the construction thereof;

Figure 8 is a rear elevation of the right-hand frame of the attachment;

Figure 9 is a top plan view of one of the chopper blades, of the improved chopping and cultivating attachment;

Figure 10 is a vertical elevation vof a fragmentary portion of the chopper blade operating mechanism of the improved attachment;

Figure 11 is a side elevation of a ridge scraper operatively secured to the front end -of an attachment frame Figure 12 is a transverse cross-section of a fragmentary portion of a chopping wheel constituting an operative component of the attachment and shows in detail the manner in which the tires of the wheel are adjustably connected to the spoke formation;

Figure 13 is a diagrammatic cross-section of fragmentary portions of the wheel and wheelsupporting frame showing the manner in which the wheel is adjustably mounted in the frame; and

Figure 14 is a side elevation of a fragmentary portion of the machine showing in end elevation a timing device for one of the chopping wheels.

With continued reference to the drawings, the tractor, generally indicated at I0, may be any conventional farm tractor ordinarily used to cultivate row crops, such as cotton. This tractor has a longitudinal frame II supported at one end by a rear axle I2 upon which are mounted the rear tractiony wheels I3 disposed one at each end of the rear axle and outwardly spaced from the tractor frame, and supported at its front end on a column I4 provided at its lower end with a transverse axle upon the ends of which are journaled the two closely spaced front wheels I5. The tractor is provided with an engine I6 and the conventional drive mechanism including the diierential mechanism I1, a steering wheel I8 and a hydraulic implement lift mechanism I9 including the transverse shaft 20 having crank arms 2l disposed one at each end thereof-and controlled by a manually-operated lever 22.

The tractor normally carries two sets of cultivating plows or hoes, not illustrated, between the front and rear wheels, which plows are pivotally connected to the tractor frame I l and operatively connected to the crank arms 2I of the hydraulic lift by elongated links 23 disposed one at each side of the tractor frame and spaced outwardly therefrom.

As the above-described tractor mechanism is al1 conventional, and may vary in detail with tractors of different manufacture, a detailed description of the tractor, the cultivating plows or hoes and the operative connections between such plows and the tractor, is not considered to be necessary for the purposes of the present disclosure.

The improved chopping or thinning and cultivating `attachment comprises two substantially identical frames, generally indicated at 25, disposed one at each side of the tractor and projecting laterally therefrom, two substantially identical chopping or thinning wheels, generally indicated at 26, carried by the frame 25, and two -pair of ridge or row Scrapers, generally indicated at 21, also carried by the frames in advance oi the wheels 26. Also, if desired, a frame attachment band 28 may be secured around the front end of the tractor frame to suitably reinforce the tractor and facilitate the attachment of the frames 25 thereto. This band 28 may have an arcuately-curved bight or intermediate portion extending across the front end of the tractor frame and a pair of spaced-apart, parallel legs 29 extending along the sides of the frame adjacent the front end thereof to receive the attachment plates of the wheel-carrying ',framesrZE.

Each of the frames 25 includes a portion rigidly attachable to the frame of the tractor or-other vehicle provided to support the Vattachmentand a movable portion hinged to and projecting forwardly of the rigidly-mounted frame portion. The rigidly-mounted portion of each frame is :adequately braced or trussed for rigidity and vcomprises a flat plate 30 secured to the tractor -frame or to the corresponding leg.29 of U-shaped band 28, .an elongated, cylindrical strut 3l secured. at one -end to the attachment plate and projecting outwardly therefrom, anda pair of .angularly-disposed, outwardly-converging braces H32 secured at their outer ends to strut .3| intermediate the length ofthe latter and at their .in- Lner ends to corresponding ends of attachment plate 30. The struts of the two frames aredisposed Isubstantially irl-alignment with each other lland extend .horizontally from ythe corresponding sides of the tractor frame substantially perpendicular tothe longitudinal center-line` ofthe tractor. A U-shaped yoke 33 has theendsof its-'legs at :theopen end thereof rigidly securedto strut 13| and extends upwardly from the strut. One leg of the yoke is attached to the strutadjacent the Vouter .ends of bracesi32 and the other leg is .attachedat allocation substantially ltt-the midlengthposition of that portion of the strut which texends i outwardly from the braces. An lelongated :tie rod .34 isattached to the upper closed end of Yyoke :33 and extends lrearwardly to the corresponding end of the rtactorrear axle l2 to which vit is attached by suitable means, such as the .clamp `35. Apair of aligned bearing `sleeves 36 :are supported by-yoke 33, one oneach leg thereof anda shaft 31 is journaled in these bearing sleeves and is disposed above and substantially parallel to strut 13|. A .substantially-vertical post 3.8 extends betweenthe outervend of strut `3| Yand the outer end of shaft .31, and an angularly-disposed brace 39 extends from the `lower -end of :this post to the .tractor frame at a location spaced rearwardly of attachment plate Y3U. The vend of brace 39 may be connected tothe :tractor frame by a suitable attachment plate 40 Asecured to the tractor frame'and to the corresponding end of the brace. A secondary brace 4l zextends from a location'on-brace' 39 intermediate 'the length thereof to the upper end of -post 38 ^to rigidly support 'the post in upright position. 'The-braces 32, 34y Y39 and 4| thus rigidly support the strut V3l and the shaft-31 in a positionsubstantially perpendicular to the longitudinal --cen- "ter-lineof :the tractor and withv the center-line of the strut and the shaft in an upright, substantially vertical'common plane. A brace 142fextendving fbe'lowstrut '3l lfrom plate '30 tothe end of 'the outer leg of vyoke 33, supports vthe -strut in substantially horizontal position and providesA the strength necessary to lift and carry the corresponding :wheel 26 without materially deflecting 4the rigid portion ofthe frame.

VThe movable portion of the frame comprises a Vvpair of parallel frame arms-43 pivotally or hingedly secured to strut 3! by suitable means, such asthe-bearing sleeves 44 receiving the strut and rigidlysecured to the -corresponding ends of the arms 45.

arms.

apertures b y means of which the extension arms are adjustably secured in the sleeves to vary the length of the movable portion of the frame to accommodatefwheels of different diameters when necessary or desirable. The U-shaped guard 41 is'positioned somewhat below the extension arms 45, and has upwardly 'bent leg portions at its open end attached to the extension arms near the sleeve received Yportions of the extension A'respective cylindrical axis sleeve or bushing 49 is secured tothe outer end of each extension arm 45, and outwardly and downwaridly-inclined braces 50 extend Vfrom these bushings-to the legs of the guard 41 to rigidly attachthe guard to the extension arms of the Vmovable portion ofthe frame. Standards 5l are secured one to eachleg of the guard 41 adjacent vthe outer end thereof by suitable clamps 52 and a .respectivescraper53 is secured to the lower Yend of each substantially vertical 'standard 5|.

These Scrapers may be in the form of discs journaled to the alower-ends of the standard or may be in theform of suitable scraper plow shares, as maybe desired.

A short post 54 Vextends upwardly from each axle bushing 43 and a. pair -of crank arms 55 projects -radially from vshaft 31 substantially in alignment vwith posts'5`4. A crank arm 5E is secured on the innerend of shaft 31 and is adjustably connected to the externally screwthreaded extension Illl of the plow lift bar 23 by a pivoted link'51 to Vrender the bar eifective to rotate -shaft`31 when moved forwardly by the implement lift mechanism of the tractor. Lift bar extensions H0 are each slidably supported in an eye III carried at the top of a respective upright standard H2 secured to attachment plate 3D. Respectivelinks 58 connect the crank arms 55 with corresponding posts 54 so that when shaft 31 is rotated the front end of the movable portion of the frame will be pivoted upwardly aboutthe bearing sleeves 44, thereby raising the axle bushings 43 and the wheels supported thereby.

The frame arms 43 are held against lateral movement by respective U-shaped braces 59 secured at their mid-length locations to the arms "43 and at their Yends to strut 3i by-suitable bearing sleeves 60.

An axle 6| extends through the axle bushings 49 and is releasably secured therein against lengthwisemovement by suitable means, such as -the'set screws E2-threaded through suitable aper- -tures inthe bushings and bearing at their inner ends againstthe axle. A'flat-cam 63 has an aperture-therethrough receiving axle 6l and is secured on the axle against rotation relative there- `vtobysuitable means, such as the key E4. This cam is partly circularand'concentric with the axle-receiving aperture, but has a radially-extending lobe 65 which projects downwardly when the cam is mounted in operative position on the frame, and has a curved forward side and a substantiallystraight, radial rear side.

Each wheel, generally indicated at 25, comprises ahub structure, generally indicated at 55, a plurality of radially-extending, angularlyspaced spoke structures, as lgenerally indicated `on webs 84.

other,

the plants in a row and are adjustably secured to at 61, a tire structure, generally indicated at 68, and a chopping blade mechanism operatively associated with each spoke structure, and generally indicated at 69.

Hub structure 66 comprises a hollow housing i 1|) having an end wall provided with a concentric, axle-receiving aperture 1| and an external annular boss 12 concentric with aperture 1| and receiving a radial anti-friction bearing 13 the inner race of which is secured on axle 6|, and an annular wall 14 of circular shape extending from the rim of end wall 1U and having radially-directed, internally screw-threaded spoke-receiving sockets 14 therein. A detachable circular end wall 15 is secured to the open end of the housing by suitable means, such as the cap screws 16 and has a central, axle-receiving aperture 11 and an annular external boss'18 receiving radial anti-friction bearing 19. The hollow housing is thus journaled on axle 6| by the radial anti-friction bearings 13 and 19. The two end walls of the housing are disposed one at each side of cam 63 and the housing is maintained against movement lengthwise of the axle by a pair of anti-friction thrust bearings 80 disposed one between each housing end wall and the correspondving ends of a cylindrical enlargement 8| provided at the mid-length location of axle 6| and received in the axle-receiving aperture of cam 63.

Each of the spoke structures 61 incluudes a tubular member 82 secured at its inner end in the annular wall 14 of hub structure 66 and secured at its outer end to the bight portion B3 of a U-shaped bracket 84 and reinforced by welded- The two legs 85 of the U-shaped bracket 84 comprise at plates which extend rtransversely of the wheel and relatively diverge in a direction away from the end or bight portion 83. The side edges of these plates also diverge in a direction away from the bight portion, as is clearly illustrated in Figure 4, and the end edges of the legs are spaced apart a distance substantially equal to the desired spacing between hills of the row crop which the implement is used to thin,

The tire structure G8 comprises a pair of annular tires 86 of generally conical shape including radially inwardly in a direction toward each These tires are spaced apart to straddle the spoke structure brackets 84 by suitable means, such as the apertured angle brackets 81 secured to the tires 86 respectively, and bearing against the outer sides of the legs 85 of the U-shaped brackets 84 and the bolts 88 extending one vthrough .each angle bracket 81 and through a transversely-elongated slot 89 in the leg of the U-shaped bracket, as clearly illustrated in Figure 12. In operation, the tires 86 are used to flatten and compact the soil along the two opposite sides of each row of plants and the distance between the two tires is made adjustable since it is desirable to space the compacted area from the plants by diierent distances incident to the size of the plants and other factors. Each tire 86 has a plurality of ground-engaging cleats 9|! secured to its outer edge so that even rotation of the thinning or chopping wheels will be maintained at all times. These cleats are preferably formed integrally with or permanently secured to the tire-attaching angle brackets 81 for facility in the construction and assembly of the device, `although intermediate cleats'may be secured to the tires by special brackets 9| disposed midway between each two adjacent angle brackets 81, if desired.

Each unit 69 of the chopping or thinning mechanism comprises a pair of flat, opposed plates or blades 9| having beveled inner edges, one pair of such plates being disposed Within each U- shaped bracket 84 of each of the several spoke structures in the wheel. In the wheel illustrated in Figure 2, there are twelve such spoke structures, but this number may be varied as may be found necessary or desirable. Each blade 9| is secured at its upper or inner side and adjacent its outer end to a pair of parallel angle bars 92, each having a portion substantially perpendicular to the plate to which it is attached and a portion substantially parallel to such plate and extending beyond the inner beveled edge of the corresponding plate.` The outer portions of these angle bars parallel to the blades are slidably received in spaced-apart, transverse apertures provided in a generally rectangular body 93 extending between the legs 85 of the U-shaped bracket 84 and secured at its ends thereto at approximately the mid-length positions of the legs. The angle bars 92 thus guide the blades for reciprocating movements toward and away from each other so that the blades may be forced apart to allow plants to pass therebetween, or may be brought together to sever the plants at a particular location in the row. These blades are spaced inwardly of the tires 86 a distance such that they normally pass through the ridge of the row slightly below the upper surface of the ridge. An elongated, cylindrical plunger 94 is slidably mounted in the tubular portion 82 of the aXle structure and is provided at its upper end with an apertured bifurcation or fork 95 in which is journaled a roller 96, preferably an anti-friction bearing, bearing peripherally on the outer surface of cam 63. With this construction, the plunger 94 is forced outwardly of the spoke structure by the cam lobe 65 each time the wheel rotates about the cam. When roller 96 passes over the tip of the cam lobe and reaches a position along the flat side of the lobe, the plunger is forced inwardly by a suitable compression spring 91, which surrounds the plunger between an annular abutment collar 98 secured in the tubular portion of the spoke structure and a collar 99 secured on the plunger inwardly of the collar 98.1-It will be noted in Figure 3 that the tip of the cam lobe 65 is displaced somewhat ahead, in the direction of wheel rotation, of a vertical line extending through the axis of rotation of the wheel so that the roller 96 may move inwardly to bring the blades 9| together co-incidentally with the particular spoke structure reaching a substantially vertical position as the wheel rotates.

The lower end of plunger 94 is operatively connected to the lblades 9| by a pair of links |98, pivotally connected at their inner ends to the cuter end of the plunger by a pivot pin ||3| extending through aligned apertures in the corresponding ends of the links and the plunger, and pivotally connected at their outer ends to the respective blades 9| by pins |92 extending through aligned apertures in the outer ends of the links and in respective bracket plates |03 secured one to each of the blades 9|.

A pair of spreader links |94 are pivotally connected at their outer ends by a common pivot pin |05 to the outer ends of a pair of parallel eX- tensions |06, extending from the tubular portion 82 of the spoke structure 4through the inner portion of the bracket 84, and are pivotally connected .at their einnerfends" respectively "to -.the two vlinks by respective pivot pins |01.

With ythis constructionfafter the roller 96 has 1passed-thetip of .the cam lobe and then moved `inwardly bythe spring 91, thecontour of the cam 'until the roller again passes over the tip of the cam lobe and the blades are brought sharply to- :gether .by 'the-stored .energyof spring 91. The

.diameter `of the wheel is selectedand the .spoke `structures are angularly spacedso that the choplpingaction will take place at the desired intervals along the row, thereby thinning the crop, such as cotton, into equally-spaced hills having a desired :number of plants .inyeach hill.

The ;operation of the chopping mechanism is timed .by `rotationally adjusting the corresponding axles 8| and associated cams B3. For this :purpose arespective armor loop '|00 is secured to and projects perpendicularly outward from ,each axle, preferably adjacent the inner end thereof. -A substantially vertical post |09 is rigidly secured to the adjacent frame members 45 :and 41 near the inner end of each axle by suitable means, such as the gusset plates or braces l0 and extends downwardly belowthe axle, and an adjustable link is pivotally connectedat its lower end to the lower end of post |09 and at its upper end to theouter end of loop |08. Link comprises two arms disposed in longitudinal alignment ywith respective eyes on their outer 'ends .pivotally connected to the post and looprespectively and externally screw threaded adjacent ends connected by an internally screw-threaded twin fbuckle ||2, so that the link can be lengthcned or shortened to adjustably rotate the axles .and associated cams.

The timing devices are also effective to hold the axles 'and associated cams in adjusted position against accidental rotation.

In the operation of the entire mechanism, as the tractor passes along the rows of plants the conventional plows or hoes cultivate the middles of the rows loosening the soil and destroying weeds, the two pair-ofscrapers pass along the two rows being cultivated, onescraper being disposed at each side of each row, to trim the ridges to a a desired cross-sectional shape, and the tires of the .wheels then pass along the upper surfaces of the ridges ilattening and compacting the earth around the roots of the plants. As the wheels pass along the rows the chopper mechanisms operate continuously and automatically to destroy .the unwanted plants, and leave hills spacedapart a desired distance and with a desired number of plants `remainingin each hill, this operation being necessary because of the necessity of planting a muchgreater number of seed than the .desired number of plants in order to besure that a Sunicient number of .plants will sprout and mature. This chopping or thinning operation is, of course, carried out while the .plants are still in an early stage of growth, the plants removed makingroom for the growth of the retained plants andthe total number of plants being reduced to a figure which the soil will adequately support.

The invention may be embodied in other speciiic forms without departing from the spirit oressential,characteristics thereof. The present embodiment is, therefore, to be considered inall respects as illustrative and not restrictive, the

appended claims. rather'than by the foregoing description, andzall changes which come within the meaning and range of equivalency of the claims are, therefore, intended to be embraced therein.

'What is claimed is:

1. A 'cotton chopper wheel comprising a hub structure, angularly-spaced spokes projecting radially from said hub structure, U-shaped brackets secured to the outer ends of corresponding spokes, a pair of spaced-apart, conicallyshaped tires secured to said brackets, a pair of oppositely-disposed chopping blades in each bracket, means mounting each pair of blades on the corresponding bracket for movement of such blades toward and away from each other, camoperated means extending along the corresponding spokes to each pair of blades to successively move the blades apart as said wheel rotates, and spring means operatively connected to the respective cam-operated means to successively move said blades together after they have been moved apart by said cam-operated means.

'2. A cotton chopper wheel comprising a hub structure, a pair of conically-shaped, spacedapart tiresconcentric'with said hub structure, angularlyspaced-apart spokes projecting radially from said hub structure, U-shaped'brackets connecting saidtires'to the outer ends of said spokes,apair of chopper blades mounted within each of said brackets vfor movement toward and away from each other, 'and a reciprocatory plunger operatively connected fto v'each pair of blades for effecting the movement of the latter.

3. A cotton chopper l'wheel `comprising a hub structure, aplurality of spokes projecting radially from said hub structure, bracket means arranged adjacent eachof the'outer ends of said spokes vand secured thereto, spaced apart tires concentric Vwith said hub structure and xedly secured to said 'bracket means, a pair of chopper blades mounted within each of said bracket vmeans for movement toward and away from each other, and a reciprocatory plunger operatively connected to each pair of blades for effecting the movement ofthe latter.

4. A cotton chopperfwheel comprising a hub structure, a plurality of spokes projecting radially from said "hub structure, bracket means arranged adjacent each of the outer ends of said spokes and vsecured thereto, spaced apart tires concentric with -said hub structure and xedly vsecured to said bracket means, a pair of chopper bladesmounted Vwithin each of said bracket means for movement toward and away from each other, cam operated means operatively connected to each pair of blades for effecting the movement of said blades away from each other, and spring means `operatively connected to said cam voperated means for effecting the movement of eachpair of yblades toward each other.

LUTHER B'. SWAFFORD.

REFERENCES CITED The followingreferences are of record in the le of this patent:

UNITED STATES PATENTS y Date 

